Pulpwood-water slurry is the medium which is subjected to a chemical or mechanical operation in nearly every phase of pulp and paper manufacture. The relative amount by weight of pulp suspended in water, i.e., the consistency of the slurry, is a key parameter which must be accurately monitored and controlled in the efficient operation of such processes as pulping, bleaching, and papermaking. The various plant processes are usually designed around optimal values of consistency. In the interests of economy and quality control, attempts are made to maintain the optimal slurry consistency values throughout the manufacturing plant. Consistency is normally defined as the weight percentage of fibrous material suspended in the slurry. In practice, slurry consistencies in the range from about 1 to about 15% are encountered in commercial pulp and paper operation.